What Could Have Been: Originally, there were plans for five full seasons. If not for the cancellation, the second and following seasons could have depicted history with the same eye for details as the first one. To quote creator Bruno Heller:
"The second [season] was going to end with the death of Brutus. Third and fourth season would be set in Egypt. Fifth was going to be the rise of the messiah in Palestine. But because we got the heads-up that the second season would be it, I telescoped the third and fourth season into the second one, which accounts for the blazing speed we go through history near the end."
Word of God: According to the creators, Vorenus survives his wound in the series finale, and goes into hiding with his family somewhere in Germania. A feature-length movie that started out from this point was in the works, but apparently succumbed to Development Hell.